1. Field of the Invention
This invention relates to sulfurized olefins and in particular to modified polysulfurized olefins used in lubricating oil compositions and to a method for preparing the same.
2. Description of the Prior Art
Organic sulfur compounds have been known as additives for lubricating oils. These compounds provide extreme pressure properties to lubricants especially under high speed shock conditions. Unfortunately, the presence of elemental or "hostile" sulfur in lubricating oils often causes considerable corrosion of metals, particularly copper. Since lubricating oils often operate at relatively high temperatures, thermally unstable sulfur compounds may break down resulting in loss of the extreme pressure property and in increased metal corrosion. In U.S. Pat. No. 2,708,199, there is disclosed a method of producing organic polysulfides from olefins having from 6 to 30 carbon atoms resulting in polymers of the olefin containing 2 to 3 sulfur atoms per unsaturated bond of the olefin. However, without proper control of the reaction conditions, the resulting compound may be highly corrosive and unstable. Moreover, if olefins of less than 6 carbon atoms were used in this process, oil insoluble products would be obtained.